A wafer can be irradiated by one or more charged particle beams during the manufacturing process of the wafer and even after the end of the manufacturing process of the wafer.
One unwanted side effect of the irradiation is the charging the wafer. The charging can be reduced and even eliminated by grounding the wafer.
A wafer may have a backside insulating layer that may prevent the grounding of the wafer. In order to allow the grounding there is a need to form holes in the backside insulating layer.
The Holes may be formed in the backside insulating layer by zapping the backside insulating layer. The zapping includes supplying high power voltage pulses (referred to as zapping pulses) to the backside insulating layer. The zapping pulses cause a breakdown of the backside insulating layer.
The zapping process is a destructive process that damages the wafer.
There is a growing need to reduce the damage caused by the zapping pulses.